#include<bits/stdc++.h>
#define ONLINE_JUDGE
#define ll long long
#define ull unsigned long long
using namespace std;

const int N = 1e6 + 10, INF = 0x3f3f3f3f;

int n, s;
int a[N];

void solve()
{
    cin >> n >> s;
    for (int i = 1;i <= n;i++)
        cin >> a[i];
    for (int i = 1;i <= n;i++)
        if (a[i] - a[i - 1] > s) { cout << "No"; return; }
    cout << "Yes";
}

signed main()
{
    // ios::sync_with_stdio(0);
    // cin.tie(0);cout.tie(0);
#ifndef ONLINE_JUDGE
    std::istringstream in(R"()");
    std::cin.rdbuf(in.rdbuf());
#endif
    int T = 1;
    //cin>>T;
    for (int i = 1;i <= T;i++) {
        solve();
    }
}